added description for greetbot

GreetBot/README.md

@@ -0,0 +1,11 @@
+# GreetBot
+
+This bot greets every time it enters a room.
+
+On line 33 you can change the code after "mbody=" to add your own greeting:
+
+    self.send_message(mto=self.room, mbody='collective conditions', mtype='groupchat')
+    
+To run this bot, type the following command in your terminal:
+
+    python3 greet.py -d -j greetbot@conversejs.org -r muc_name@muc.vvvvvvaria.org -n greetbot -p testing